I am knitting my first sweater. could anyone help to decipher the instructions?

ive been knitting my first turtleneck sweater after knitting a lot of flat projects. i have finished the bulk of the project but i am unsure what the last part (listed under collar) is instructing me to do. it says to:

"Sew right shoulder seam. With RS of work facing and smaller needles, pick up and knit 21 (21-21-23-25-25) sts down left Front neck edge. K18 (20-20-22-24-26) from front st holder. Pick up and knit 21 (21-21-23-25-25) sts up right front neck edge. K30 (32-32-34-36-38) from Back st holder. 90 (94-94-102-110-114) sts.
Work in (K2. P2) ribbing, as given for Back for 7 ins [18 cm], ending with WS row. Cast off in rib.

Sew left shoulder and Collar seams, reversing last 4 ins [10 cm] for turn back.
Sew in Sleeves. Sew side and sleeve seams."

i dont understand this as it does not say to do the ribbing for the front even though there is supposed to be ribbing all around. also, it says to "pick up and knit down/up left/right front neck edge which i assume means to pick up 21 sts on the left/right curved area between the seam and the front st holder?

also, i am unsure of what “reversing last 4 ins for turn back” means.

If anyone could explain any of this to me it would be a great help!

link for context!

Thanks.

Hi lily-less,
The pattern asks you to sew only the right side shoulder seam to enable you to pick up and knit all around the neck area,front and back, so you can knit the turtle neck collar as a flat piece of knitting which is then seamed afterwards to close it.
With the RS facing you pick up and knit the correct amount of sts for the size you are making along the left front neck towards some stitches you have on a holder, knit across those sts for the front, pick up and knit the same amount of sts across the right front neck towards the sts on hold for the back then knit those back neck sts off the holder. Check you have the correct amount of sts for the size you’re making then work 2x2 rib for 7’’ casting off in rib.
When you seam the collar, start sewing from the WS but turn the work to continue sewing from the RS when there is 4’’ left so the seam will be underneath when you fold back the turtleneck.
If you have circular needles or dpns in the correct size you can just sew both the L and R shoulder seams, pick up the correct amount of sts and knit across the sts on holders for the size you are making then knit the collar in one piece - no collar seam to bother about!!
Hope this helps, good luck with it - you’re almost finished :grinning: